For the optimization optimisation we define different areas of the geometry. These are mainly Design and Nondesign spaces.
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The Design Spaceis the most important space and complies with the imported/created solid CAD geometry. It includes any space where material is allowed to be or has to be, to provide maximal freedom for the algorithm. If the design space is limited, so is the optimization optimisation algorithm and the optimization optimisation potential is reduced.
The Nondesign space contains the necessary geometries of the part. Any part for which you need a clearly defined geometry should be a Nondesign space. To create Nondesign spaces the geometry needs to be either split into cells or a constraint is applied to a surface, edge or point which automatically creates a Nondesign space for this geometry. Cells are partitions of the design space. They can be created with the split tool, directly in the Nondesign selection tool or with a Boolean operation using two or more solids.
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Intersections are necessary after each optimization optimisation to get the defined surfaces of the Nondesign spaces. These defined shapes are needed for example for the post processing of the manufacturing process.
To realize a post processing of additive manufactured parts an Manufacturing Offset needs to be considered for the functional surfaces. This needs to be added to the Nondesign spaces and therefore to the Design space before an optimization optimisation is started. Afterwards it is very complicated and time consuming to add such an offset to the result file.
TippTip: Avoidance of stress rising on Design space boundaries. Sometimes it is useful to reduce the Design space a little bit for the optimization optimisation by subtracting an offset. The optimization optimisation is carried out with this reduced Design space. However, the intersection afterwards is done with the originally defined Design space in order to avoid sharp edges and thus stress risings. This way you avoid stress risings on the boundaries after you have combined your optimization optimisation result with your original design space.
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